Researchers at Rice University and the Université catholique
de Louvain, Belgium, have developed a way to make flexible components for
rechargeable lithium-ion (LI) batteries from discarded silicon.
The Rice lab of materials scientist Pulickel Ajayan created
forests of nanowires from high-value but hard-to-recycle silicon. Silicon
absorbs 10 times more lithium than the carbon commonly used in LI batteries,
but because it expands and contracts as it charges and discharges, it breaks
down quickly.
The Ajayan lab reports this week in the journal Proceedings
of the National Academy of Science on its technique to make carefully arrayed
nanowires encased in electrically conducting copper and ion-conducting polymer
electrolyte into an anode. The material gives nanowires the space to grow and
shrink as needed, which prolongs their usefulness. The electrolyte also serves
as an efficient spacer between the anode and cathode.